Added automatic extended frame format recognition.

Most SocketCAN userspace tools (like cansend) recognize the EFF by the
stringlength of the given CAN-ID: 3 -> SFF , 8 -> EFF.
This was missing in the candump filter definition and therefore the
values had to be specified with the CAN_EFF_FLAG set in the value, e.g.
92345678 for the extended CAN-ID 12345678 - this was not really nice.

Now the filtersets for extended frames can be specified as expected:
12345678:1FFFFFFF to filter for only 12345678 extended CAN-ID
000000AA:1FFFFFFF to filter for only AA extended CAN-ID.

diff --git a/candump.c b/candump.c
index 4d96536654d26db3f3b6dba51b36f6fcd09f429a..09f455cd28f342d6eed928d038594e0b370d72d6 100644 (file)
--- a/candump.c
+++ b/candump.c
@@ -116,12 +116,16 @@ void print_usage(char *prg)
        fprintf(stderr, " <can_id>:<can_mask> (matches when <received_can_id> & mask == can_id & mask)\n");
        fprintf(stderr, " <can_id>~<can_mask> (matches when <received_can_id> & mask != can_id & mask)\n");
        fprintf(stderr, " #<error_mask>       (set error frame filter, see include/linux/can/error.h)\n");
+       fprintf(stderr, "\nCAN IDs, masks and data content are given and expected in hexadecimal values.\n");
+       fprintf(stderr, "When can_id and can_mask are both 8 digits, they are assumed to be 29 bit EFF.\n");
+       fprintf(stderr, "Without any given filter all data frames are received ('0:0' default filter).\n");
        fprintf(stderr, "\nUse interface name '%s' to receive from all CAN interfaces.\n", ANYDEV);
-       fprintf(stderr, "CAN IDs, masks and data content are given and expected in hexadecimal values.\n");
        fprintf(stderr, "\nExamples:\n");
        fprintf(stderr, "%s -c -c -ta can0,123:7FF,400:700,#000000FF can2,400~7F0 can3 can8\n", prg);
        fprintf(stderr, "%s -l any,0~0,#FFFFFFFF    (log only error frames but no(!) data frames)\n", prg);
+       fprintf(stderr, "%s -l any,0:0,#FFFFFFFF    (log error frames and also all data frames)\n", prg);
        fprintf(stderr, "%s vcan2,92345678:9FFFFFFF (match only for extended CAN ID 12345678)\n", prg);
+       fprintf(stderr, "%s vcan2,12345678:1FFFFFFF (analog to above due to 8 digit value length)\n", prg);
        fprintf(stderr, "\n");
 }
 
@@ -179,6 +183,21 @@ int idx2dindex(int ifidx, int socket) {
        return i;
 }
 
+canid_t checkeff(char *ptr, char *nptr)
+{
+       int len;
+
+       if (nptr)
+               len = nptr - ptr;
+       else
+               len = strlen(ptr);
+
+       if (len == 17 && (ptr[8] == ':' || ptr[8] == '~'))
+               return CAN_EFF_FLAG;
+       else
+               return 0;
+}
+
 int main(int argc, char **argv)
 {
        fd_set rdfs;
@@ -194,6 +213,7 @@ int main(int argc, char **argv)
        int opt, ret;
        int currmax, numfilter;
        char *ptr, *nptr;
+       canid_t eff;
        struct sockaddr_can addr;
        struct can_filter rfilter[MAXFILTER];
        can_err_mask_t err_mask;
@@ -364,13 +384,19 @@ int main(int argc, char **argv)
                                           &rfilter[numfilter].can_id, 
                                           (long unsigned int *)
                                           &rfilter[numfilter].can_mask) == 2) {
+                                       eff = checkeff(ptr, nptr);
+                                       rfilter[numfilter].can_id |= eff;
+                                       rfilter[numfilter].can_mask |= eff;
                                        numfilter++;
                                } else if (sscanf(ptr, "%lx~%lx",
                                                  (long unsigned int *)
                                                  &rfilter[numfilter].can_id, 
                                                  (long unsigned int *)
                                                  &rfilter[numfilter].can_mask) == 2) {
-                                       rfilter[numfilter].can_id |= CAN_INV_FILTER;
+                                       rfilter[numfilter].can_id |= CAN_INV_FILTER;
+                                       eff = checkeff(ptr, nptr);
+                                       rfilter[numfilter].can_id |= eff;
+                                       rfilter[numfilter].can_mask |= eff;
                                        numfilter++;
                                } else if (sscanf(ptr, "#%lx",
                                                  (long unsigned int *)&err_mask) != 1) {